Btrfs: introduce a tree for items that map UUIDs to something

[platform/adaptation/renesas_rcar/renesas_kernel.git] / fs / btrfs / ctree.h

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index f697d00..429c54a 100644 (file)
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -91,6 +91,9 @@ struct btrfs_ordered_sum;
 /* holds quota configuration and tracking */
 #define BTRFS_QUOTA_TREE_OBJECTID 8ULL
 
+/* for storing items that use the BTRFS_UUID_KEY* types */
+#define BTRFS_UUID_TREE_OBJECTID 9ULL
+
 /* for storing balance parameters in the root tree */
 #define BTRFS_BALANCE_OBJECTID -4ULL
 
@@ -1943,6 +1946,19 @@ struct btrfs_ioctl_defrag_range_args {
 #define BTRFS_DEV_REPLACE_KEY  250
 
 /*
+ * Stores items that allow to quickly map UUIDs to something else.
+ * These items are part of the filesystem UUID tree.
+ * The key is built like this:
+ * (UUID_upper_64_bits, BTRFS_UUID_KEY*, UUID_lower_64_bits).
+ */
+#if BTRFS_UUID_SIZE != 16
+#error "UUID items require BTRFS_UUID_SIZE == 16!"
+#endif
+#define BTRFS_UUID_KEY_SUBVOL  251     /* for UUIDs assigned to subvols */
+#define BTRFS_UUID_KEY_RECEIVED_SUBVOL 252     /* for UUIDs assigned to
+                                                * received subvols */
+
+/*
  * string items are for debugging.  They just store a short string of
  * data in the FS
  */
@@ -3481,6 +3497,14 @@ void btrfs_check_and_init_root_item(struct btrfs_root_item *item);
 void btrfs_update_root_times(struct btrfs_trans_handle *trans,
                             struct btrfs_root *root);
 
+/* uuid-tree.c */
+int btrfs_uuid_tree_add(struct btrfs_trans_handle *trans,
+                       struct btrfs_root *uuid_root, u8 *uuid, u8 type,
+                       u64 subid);
+int btrfs_uuid_tree_rem(struct btrfs_trans_handle *trans,
+                       struct btrfs_root *uuid_root, u8 *uuid, u8 type,
+                       u64 subid);
+
 /* dir-item.c */
 int btrfs_check_dir_item_collision(struct btrfs_root *root, u64 dir,
                          const char *name, int name_len);